The Pike River Royal Commission has finished its public hearings into the 2010 New Zealand mine disaster which claimed the lives of 29 men, including two Australians.

The lawyer representing the underground mine's former chief executive Peter Whittall and five other senior managers acknowledged there were shortcomings in some of Pike River Coal's systems.

But she said it was unfair her clients had been used as scapegoats as they had consulted widely on the mine's design and operation.

She criticised the mine's former chief executive, Gordon Ward, who has refused to give evidence at the inquiry despite having left the top job only weeks before the disaster.

Final submissions this week have been harrowing for the victim's families. Many were in tears.

No bodies have been recovered from the mine, which remains closed.

The families of the 29 victims say they are confident mine safety will be improved as a result of the Royal Commission.

A spokesman for the bereaved families, Bernie Monk, says it is good to have the hearings finished.

"[I'm] very confident we'll get more safety in mines and that's one thing that'll be a heritage from Pike River families," he said.

Mr Monk says the families will now redouble their efforts to retrieve their loved ones' bodies.

"Our main objective from today is going to be recovery. We've written to the receivers and Pike River and had no replies and we're sick of it."

On Monday, a lawyer for the mining union told the commission that Pike River Coal's failure to protect its underground workers and the labour department's poor inspection system had led to the catastrophe.

The inquiry heard that a charge of corporate manslaughter should be introduced.

New Zealand state mining company Solid Energy, which is buying the Pike River Coal mine, said it wanted the Queensland Mines Inspectorate to control the inspection of high-hazard industries in New Zealand.

The Royal Commission is due to deliver its final report at the end of September.

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